Introduction

Introduction

Thank you for your interest in our cellular routers. This
application note will help you get up and running with our solution, to
serve your business. It will provide you with various applications where
these routers come in handy and how to configure them properly.

Note

This document is not intended to explain all configuration options
– see the Manual
for details.

SIM cards for mobile connectivity are required, as with using any
cellular router. All SIM cards must have data
transmission enabled and you need to know the Access Point Name (APN), which is the name of a
gateway between the mobile network and another computer network, most
often the public Internet.

Note

If not specified otherwise, all features are supported within all
cellular systems such as GPRS, UMTS, HSPA+, LTE and others.

Choosing the most suitable APN for your application is important. As
well as considering the number of units within your application. If you
have about 5 – 25 units, you can work just with our M!DGE/MG102i routers,
but if hundreds of units are required, a special leased line to service
providers or VPN concentrators can be required. See the differences in
Section “A
Standalone M!DGE/MG102i in the Center” and Section
“A
leased line to the Cellular Network Center” in the
Typical
Usage application note.

Basically, you can have five options for
choosing APN:

The public “internet” APN via
which you obtain a private and dynamic mobile IP
address. Typically, our unit needs to initiate the
connection to the Internet – i.e. the client cannot send data to this
unit without establishing some kind of connection from our unit first
(TCP, VPN tunnel, …). Also keep in mind that the obtained IP address
is always different. This APN can be suitable if you have one central
location (e.g. with public and static IP address) and the clients
connect via VPN tunnel.

The second solution is almost the same, but with a static IP address. This IP address is still
within the private IP range and is
not reachable from outside directly, because this direction is blocked
by the provider’s network firewalls. However the benefit can be that
the VPN concentrator accepts incoming VPN tunnels only from predefined
IP addresses and the rest are rejected.

Another option is to obtain a dynamic
public IP address. With these IP addresses, you can have
the communication among the units without VPN tunnels (but they can be
used) and in both directions. The only issue is that you need to
configure Dynamic DNS services for
each unit so the connections will be made via hostnames (always the
same for a given unit) and not via IP addresses (which are different).
Keep in mind that Dynamic DNS functionality can be chargeable and is
not under RACOM control.

The last general solution is to have both public and static IP
addresses. This is typically required only for the central
unit and is usually the most expensive solution. The benefit is that
you do not need to use Dynamic DNS nor rely on third party
functionality. Together with the third option, do not forget to
configure firewall rules to limit the access to your units, because
the connection is open from the Internet side.

The last, but very important option is to use private APN. The IP addresses are given to you
within a private range, they are
usually static and they cannot access the Internet, but they can reach
each other directly. The benefit is that you have full control of your
network and each unit is reachable from any other. You don’t need to
configure any VPN tunnels unless required by security reasons. Nobody
can access the network without the knowledge of APN
credentials.

M!DGE/MG102i units can also be used jointly
with our UHF/VHF routers RipEX. The network made up of RipEX
radios works within a private frequency range and is very secure and
robust. The RipEX network can be used in places where 99.9% reliability is
required. On the other hand, you can add some M!DGE/MG102i units to your
existing RipEX network here and there where it wouldn’t be essential to
have RipEX radio coverage, e.g. one very remote location, but with a good
cellular signal.

M!DGE/MG102i can be a good option as a backup
to your existing WAN connectivity. If this connectivity fails,
our router can serve as a backup internet access via the cellular network
and as soon as the primary connection is fixed, it’s activated again. With
MG102i, you can use two different SIM cards and if one connection fails,
the second can serve as a backup solution.

Our routers are equipped with the serial interface RS232 and two
Ethernet ports (MG102i has five Ethernet ports) so your application can
use both of them simultaneously. Within the RS232 interface, we support
recognizing individual protocols (Protocol
server) such as IEC101, Modbus and others so you can route the
packets based on their serial protocol’s addresses.

Both routers also support redundancy solutions so you are safe in unlikely
case of any HW failure. We can check the connectivity status and switch
between connections very fast. Both routers are fully compatible with each
other.